What is an Ankle Brachial Index (ABI) test?
An ABI test is a non-invasive physiologic study which includes bilateral segmental pressures of the lower extrmities at multiple levels. It includes Pulse Volume Recordings (PVR) which provide waveforms to analyze the quality of blood flow. ABI values can sometimes be non-diagnostic due to arterial calcification. The system used at The Foot & Ankle Center, PC called PADnet™+, solves this problem because the PVR test can uncover disease in locations where arterial calcification masks the underlying problem. It is a simple and accurate test to detect peripheral arterial disease. Complete this questionnaire to determine if you need to have an ABI performed.
Each of the components of the ABI test using PADnet™+ are described:
- Segmental Pressures: A test to evaluate and compare the systolic blood pressures in a patient’s arms and ankles (developing the ankle-brachial indices, or ABI) as well as toes (toe-brachial indices or TBI). The comparison of systolic blood pressures in a patient’s arms and great toe are often used in addition to or as a replacement of the ABI in patients with non-compressible vessels.
- PVR (Pulse Volume Recording): PVR waveforms are plethysmographic tests which provide qualitative information. Simply put, a blood pressure cuff is inflated to a level that does not interrupt arterial flow (approximately 65 mmHG). As each arterial pulse passes through the segment of artery beneath the cuff, the volume of blood causes distention of the artery. This is sensed by the cuff, which then transmits a volume change to a recorder thus providing a waveform.